The film establishes that the action takes place somewhere on the south coast of England early in WW2 with the house overlooking the sea. In several scenes, lights are blazing and no curtains are drawn. This would have been in direct contradiction of blackout regulations.
Alice uses a Kodak Brownie Reflex camera. The viewfinder shown in the movie has a landscape format although this camera uses the 4x4 square format.
The unification of Italy is quoted as being 1861 when in fact it was 10 years later, 1871. This combined with the film being set next to the white cliffs of Dover and showing an idyllic life, while London is being bombed and an invasion of England is anticipated, makes one wonder whether the scriptwriter knows anything about European history.
There are a number of key scenes set on the beach. At the time the film is set (early 1940s), the entire coastline of the south east of England was mined and access was restricted by barbed-wire barriers, all in anticipation of an expected German invasion. It would not have been possible (and indeed would have been very dangerous) to go onto the beaches below the cliffs.
The distance to London is shown on drive, but signage was removed during the war especially in coastal areas. It is also very doubtful if any private citizen would have had enough petrol ration to just drive off to London.
Frank's father is a pilot in the Royal Air Force. He tells his wife he has a new kind of plane, a twin-engine Lockheed "Ventura". The RAF did not get "Ventura"s until 1941, after the Battle of Britain, and the setting of this story. The "Ventura" was a medium bomber, and was not used on British air craft carriers. During the film's story, a British air craft carrier is reported to be sunk, with all hands. However, no British air craft carrier was sunk at this time.
Lead character, Alice (Gemma Arterton) locates where she lives as in "Kent," close to seaside town "Ramsgate" (correctly in Kent): but the recurring view seen is of the coast guard cottages that look across onto the 'Seven Sisters' cliff-faces on the South ('Downs') Sussex coastline.
Alice (Gemma Arterton) pronounces the town name "Youghal" as "YOW-all" (i.e. YOW rhyming with COW). Youghal is actually pronounced just like "y'all."
Alice stops smoking about one-quarter into the movie, very unlikely.